STRAWBERRY (summer fruiting, perpetual and alpine)
Planting to harvest time: Generally three to four months. Plants have a useful life of three years.
Yield: 25 plants sufficient for average family.
Aspect: Sunny, but alpine strawberries tolerate shade.
Climate: Cool temperate to subtropical.
Soil: Ordinary soil enriched with plenty of organic matter.
Planting and cultivation
There are three kinds of strawberry: the summer fruiting varieties; the perpetual fruiting varieties, which produce fruit over several months; and the alpines, which bear fruit all summer. They can be planted in spring, late summer and autumn. Late summer planting is best if you want plants which will give a superb performance the following year. Strawberries should be planted in a sunny position which has been well prepared by forking well-rotted compost or peat into the top 15 cm (6in) of soil. No artificial fertilizers are required. Tread the soil firm and allow it to settle for a couple of weeks before planting 45 cm (18 in) apart each way so that the crown of each plant is level with the soil surface. Water the plants well if the weather is dry. Should any plants be lifted by frost, dig them up and replant them at the correct depth. Once the flowers appear, surround the plants with a thick layer of straw or peat to keep the fruit clean. Alternatively you can surround the plants with black polythene. After fruiting, feed the plants with a proprietary tomato fertilizer which is rich in potash.
The entire stock of plants should be renewed every third year, either from your own plants or from a reputable source, and a fresh strawberry bed established in a new spot. Alpine strawberries can either be divided in early spring as you would do with an herbaceous plant, and the best pieces replanted, or you can raise new plants from seed. Alpine strawberries can also be grown as an edging to flower borders. If you want early crops oi’ strawberries, cover the plants at the start of late winter with either cloches or polythene tunnels. Some ventilation will be necessary during the flowering period to ensure pollination.
Pruning and training
The runners from summer fruiting varieties should be cut off close to the parent plants when they appear, unless you wish to use them to increase your stock of plants. Perpetual fruiting varieties do not normally produce many runners, but those that do bear flowers and fruit and should be retained. Alpine strawberries have no runners. Summer fruiting varieties should have all their leaves cut off and the foliage burned after they finish fruiting in order to prevent disease. Perpetual fruiting straw-berries should have their leaves removed in autumn. Alpines need no such treatment. If you have used straw to surround the strawberries, this should be lifted and burned.
Pests and diseases
Aphids, botrytis (grey mould), birds (protect with netting once fruit has formed), mildew, slugs, snails, strawberry caterpillars (spray with insecticide after flowering) and strawberry virus disease (leaves are small, plants are stunted: there is no cure – so dig up and burn).
(1) If the strawberry plants are dry when you receive them, soak them in water for ten minutes. Then set the plants out so that the crown of the plant is just at ground level and the roots are well spread out. Firm the soil around the plant with your fingers. Set out other plants at a distance of 45 cm (18 in) each way.
(2) The runners from the summer fruiting varieties should be cut off close to the parent plants when they appear, unless you wish to use them to increase your stock of plants. If you are in doubt about the health of your stock, it is far better to buy new plants from a reputable source every third year, as disease is readily transmitted from the parent plants to the runners.
(3) Summer fruiting varieties need to have all their leaves cut off and the foliage burned immediately they finish producing fruit in order to prevent disease. Remove the leaves of perpetual varieties in autumn. If you have used straw to surround the strawberries, lift this and burn it along with the leaves.